In a free webinar tomorrow at 10AM Pacific, Professor of Finance Dr Sanjiv Das will present, "Using R for Analyzing Loans, Portfolios and Risk: From Academic Theory to Financial Practice". I saw a version of Dr Das's talk a couple of months ago at the Bay Area R User Group ... [Read more...]

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Dr. Patrick Burns is the founder of Burns Statistics, providing consulting and bespoke software specializing in quantitative finance, programming in the S language, and optimization via genetic algorithms and simulated annealing. Patrick has written m... [Read more...]

How wide is the darkness? Uses of models The main way models are used is to: shine light on the “truth” We create and use a model to learn how some part of the world works. But there is a another use of models that is unfortunately rare — a use ... [Read more...]

A new package OpenStreetMap has been released to CRAN this week which is designed to allow you to easily add satellite imagery, or open street maps to your plots. Raster maps are a great way to add context to your spatial data with a minimum outlay of effort. The syntax ... [Read more...]

Version 1.6 has just been submitted to CRAN and I will post the source here in the dropbox. Version 1.6 will probably be stable for a long time unless I find a bug. The main additions I made were adding a few functions to make some things easier, and I converted two ... [Read more...]

ThinkStats (by Allen B. Downey) is a good book to get you familiar with statistics (and even Python, if you’ve done some scripting in other languages). I thought it would be interesting to present some of the examples & exercises in the book in R. Why? Well, once you’ve ... [Read more...]

It’s often easier to understand a chart than a table. So why is it still so hard to make a simple data graphic, and why am I still bombarded by mind-numbing reams of raw numbers? (Yeah, I love ggplot2 to death. But sometimes I want a little more interaction, ... [Read more...]

Running DEoptim in parallel has been on the development team's wishlist for awhile.  It had not been a priority though, because none of us have personally needed it.  An opportunity arose when Kris Boudt approached me about collaborating to a... [Read more...]

It has been a wonderful week in Roma, a mix of pleasant work and enjoyable free-time! I gave the ABC advanced course for the second time in a month so it did not require much in terms of preparation and there was a good sized audience with attentive (if too ... [Read more...]

For those who have not read the seminal works of Tufte and Cleveland, please hang your heads in shame. To salvage some sense of self-worth, you can then head over to Solomon Messing’s blog where he is starting a series on data visualization based on ... [Read more...]

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This announcement was made by Hadley Wickham in the [R-pkgs] mailing list. ———————- # ggplot2 ggplot2 is a plotting system for R, [Read more...]

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After my post on making dotplots with concise code using plyr and ggplot, I got an email from my dad who practices immigration law and runs a website with a variety of immigration resources and tools.  He pointed out that the … Continue reading → [Read more...]

Spurious Regression problem dates back to Yule (1926): “Why Do We Sometimes Get Nonsense Correlations between Time-series?”. Lets see what is the problem, and how can we fix it. I am using Morgan Stanley (MS) symbol for illustration, pre-crisis time … Continue reading → [Read more...]

How to set the default seed for the RNG behind the runif(), sample() and other command? Well, there are several ways doing that (like setting .Random.seed directly), but as the documentation states, set.seed() is the recommended way to specify seeds.__ ?set.seed__ set.seed(0)__ runif(1,0,1)[1] 0.8966972__ set.seed(0)__ runif(1,0,1)[1] 0.8966972__ ... [Read more...]

I'm playing around with some personal data collection, and using some cloud computing to visualize it. Following the directions in this blog post, I've written an R function which visualizes data it draws from a Google Docs spreadsheet, and uploaded it... [Read more...]

Interactive Brokers is a discount brokerage that provides a good API for programatically accessing their platform.  The purpose of this post is to create an application that will capture tick level data and save that data into a database for futur... [Read more...]